My (admittedly limited) experience with Atlas O switches placed on a local club layout was "mixed" at best; frustrating at worst. The Atlas O track on that modular layout was favored by most club members worked well and looked great, but ...
The spring-loaded Atlas O switches performed an anti-derail action when a locomotive passed across it, but some lightweight freight cars (empty gondolas and flat cars) did not have enough "heft" to push the swivel rail to the appropriate position -- thus a derail. We bought two Atlas O electric anti-derail kits to test the benefit of electrified swivel rail action, but never installed them because (unfortunately) the club disbanded soon after.
The anti-derail function of Lionel Fastrack switches were very reliable - never a derailment.
Mike Mottler LCCA 12394